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                    Field Names
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            <h1>Field Data</h1>


            <h2>$this->db->list_fields()</h2>
            <p>Returns an array containing the field names. This query can be called two ways:</p>


            <p>1. You can supply the table name and call it from the <dfn>$this->db-></dfn> object:</p>

            <code>
                $fields = $this->db->list_fields('table_name');<br /><br />

                foreach ($fields as $field)<br />
                {<br />
                &nbsp;&nbsp;&nbsp;echo $field;<br />
                }
            </code>

            <p>2. You can gather the field names associated with any query you run by calling the function
                from your query result object:</p>

            <code>
                $query = $this->db->query('SELECT * FROM some_table');
                <br /><br />

                foreach ($query->list_fields() as $field)<br />
                {<br />
                &nbsp;&nbsp;&nbsp;echo $field;<br />
                }
            </code>


            <h2>$this->db->field_exists()</h2>

            <p>Sometimes it's helpful to know whether a particular field exists before performing an action.
                Returns a boolean TRUE/FALSE.  Usage example:</p>

            <code>
                if ($this->db->field_exists('field_name', 'table_name'))<br />
                {<br />
                &nbsp;&nbsp; // some code...<br />
                }
            </code>

            <p>Note:  Replace <em>field_name</em> with the name of the column you are looking for, and replace
                <em>table_name</em> with the name of the table you are looking for.</p>


            <h2>$this->db->field_data()</h2>
            <p>Returns an array of objects containing field information.</p>
            <p>Sometimes it's helpful to gather the field names or other metadata, like the column type, max length, etc.</p>


            <p class="important">Note: Not all databases provide meta-data.</p>

            <p>Usage example:</p>

            <code>
                $fields = $this->db->field_data('table_name');<br /><br />

                foreach ($fields as $field)<br />
                {<br />
                &nbsp;&nbsp;&nbsp;echo $field->name;<br />
                &nbsp;&nbsp;&nbsp;echo $field->type;<br />
                &nbsp;&nbsp;&nbsp;echo $field->max_length;<br />
                &nbsp;&nbsp;&nbsp;echo $field->primary_key;<br />
                }
            </code>

            <p>If you have run a query already you can use the result object instead of supplying the table name:</p>

            <code>
                $query = $this->db->query("YOUR QUERY");<br />
                $fields = $query->field_data();
            </code>


            <p>The following data is available from this function if supported by your database:</p>

            <ul>
                <li>name - column name</li>
                <li>max_length - maximum length of the column</li>
                <li>primary_key - 1 if the column is a primary key</li>
                <li>type - the type of the column</li>
            </ul>


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